The present invention relates to a bumper for a motor vehicle.
Nothing in the following discussion of the state of the art is to be construed as an admission of prior art.
Bumpers for motor vehicles are constructed to prevent damage to the vehicle body structure in the event of a crash or impact at low speed (up to 16 km/h) and directly affect the type of damage to a vehicle and the damage assessment. As a result, the construction of bumpers is used for categorizing vehicles in certain insurance classes. The lower the expected repair costs in the event of a collision, the better the insurance classification.
Bumpers are typically arranged across the front and rear of a motor vehicle and include a cross member which is coupled to the side rails of the vehicle body via crash boxes. The crash boxes may also form part of the side rails and are configured in this case as repair solution. Oftentimes, the cross member has a hat-shaped profile having flanks that can be connected by a closing metal sheet to prevent inversion of the flanks. Also known are cross members in the form of single-cell or multi-cell extruded or rolled profiles.
Bumpers are currently tested by offset barrier crash tests, whereby in the event of a front-offset crash test the vehicle strikes a barrier that is slanted by 10°, whereas in the event of an rear-offset crash, the vehicle is hit by an impact car which strikes the test vehicle at an angle of 10° in relation to the vehicle length axis. In view of the design of current vehicles, the barriers strike directly the crash boxes so that the main work, i.e. almost the entire energy, must be absorbed in these crash tests by the crash boxes. The cross member assumes hereby the task to provide in further test requirements, such as the pendulum test, sufficient support to the pendulum and to ensure the integrity between the crash boxes and side rails in the event of high-speed crashes.
Conventional bumpers suffer shortcomings because in order to meet the standards of older or current crash repair tests, their overall weight has increased in an undesired manner.
It would therefore be desirable and advantageous to provide an improved vehicle bumper which obviates prior art shortcomings.